The engine is mounted directly to the drive... so there's not really any "Mounts" in this system.
But, on that note... I'm guessing the rattling you are hearing in the vid is the rear ladder. It's a noisy thing at idle. (normal)
As far as the brakes... no, there isn't really a kit... but you can buy any part you need. I got a swing tongue from Gander Mtn for $70 as I recall... and the rest of the parts were bought from ebay. It was 2 drums, backs, battery, switch and some wire. I think I was into it for less than $300 when it was all done.